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remainder it will be allowed, represents many years of hard work to come ; and how the scheme is to be further prosecuted, and at the same time to defray the annual charge of interest on calls, is incomprehen sible. It will be, when completed, a noble monument, and creditable to the gifted people who have undertaken it. That it can become a paying concern, we must question. The probability is that the finan cial machinery which has hitherto floated and supported the edifice must give way before its completion, and that the supplies will fail; but as the French seem to make its completion a point of national honour, it is not improbable that the Government will ultimately assist the company by adequate subventions. The present monetary crisis having extended to the Bourse, as we may see by the difficulty in which the mammoth Credit Mobilier and the Immobiliere are placed, must increase the difficulties of the situation. * * ♦ * The Mersey and Channel Tunnels have made no advance during the past season. Mr. Remington’s project for tunnelling the channel from Dungeness Point in preference to taking a more easterly line looks well. He claims for his idea the advantages of a lower landfall, a wealden clay substratum in which to drive his headings, and a bank at nearly half the space of the channel which can be made available as a Point d’Appui, as well as for a permanent shaft. His line would be slightly longer than that of the Dover project, where the land is high and the substrata chalk, being loose and water bearing. In the meantime there is a plan on foot which is likely to find supporters immediately on the return of confidence, inspired by the president of the Institute, and which will probably take the same position with regard to Mr. Remington’s scheme that the summit railway of Mr. Brunlce’s does to the Cenis Tunnel. It is that of a railway ferry, the boats to be 600 feet long to carry the trains bodily across. Mr. Fowler proposes to run out a pier parallel to the Admiralty Pier at Dover. Between these moles the boats will lay when receiving and discharging their trains. We are not yet informed how the difficulties arising from the rise and fall of a 22 foot tide are to be combatted; on the French side the Calais pier is to be considerably extended on cast- iron screw piles. This is the most utterly unpleasant channel passage around our coasts. There is here continually a chopping sea, perfectly destructive to the comfort of all passengers but those who are born sailors. Nausea will by this plan be all but eliminated, for, with such long boats in such a sea, the pitching of the vessel will be m7, while the rolling will be reduced to a minimum. The absence of a cordial understanding between the two nations alone have so long pre vented the improvement of this very important service, the traffic by which is as enormous as the means for conducting it are wanting and contemptable. The person who remodels these arrangements in a satis factory manner will be the most popular man of the day in France as well as in England. The project for the crossing of the Mersey is even farther from a aatisfactory solution than those last mentioned. Mr. Brunlee’s design fora bridge at the Runcorn side of the town, as well as Mr. FowlePs tunnel, have equally fallen through. Mr. Hawkshaw has conceived a new idea here, that of a tunnel from New Brighton to Bootle, which he believes he can accomplish at a much less cost than any other scheme, as he will then find a more tractable rock than elsewhere : we may, however, prophecy that the Liverpool merchants are too good judges of the value of time to commit themselves to such an out of the way route, which one of Mr. Lister’s circular ferry-boats will beat in a canter. They like to see their money’s worth; they are accustomed to the stately ships. They will, with their present aesthetic aspirations, prefer the stately bridge to a burrow under their river’s bed, even though it cost something more than the latter. In ten years more we may see the enterprise floated, meanwhile they are setting themselves to improve their ferry approaches and accessories. Mr. Hawkshaw has placed a specification of his tunnel scheme before the Corporation, who have acknowledged its receipt with thanks. More than this we do not know at present. * * * * The masonry of the Royal Engineers’ work called the Land Fort, one of the new defences of the Medway, has sunk bodily into the ground, after having been carried to a height of eight feet above the surface level. This is an event hardly creditable in the face of the well-known scientific attainments of the distinguished body of men who are account able for the result. All are aware that cloister education has never before been carried to so high a pitch in that corps. Can it be that, in their enthusiasm for the theoretical, they have lost sight of the practical, and become disciples of Berkley’s theory ? No matter ! Turkey is a country in which there is much to be done, and, if we are correctly informed by the press, the Sultan in now engaged in preparing (Extensive schemes for the introduction of railways. In Russia also there is fair expectation of railway work in prospect. Berths in either of these countries should be narrowly watched. Russia pays capable men better than any country in Europe. China and Japan are still without railways, and will, doubtless, ere long, call for their introduction. Japan has already given orders in England for guns and ships; the railway sooner or later, must follow. The railway pioneer, in either of these countries, may demand his own terms. The incomes of English bankers and brokers in China are very large. The most novel feature in railway works in London is the advance of a leg of the Midland system as far as Saint Pancras, which here takes up its habitation in a first class metropolitan station. We cannot help admiring the successful strides and dash of this spirited company, formerly confined to a few central shires, but now ubiquitous, while, at the same time, we express our surprise to see it settling so grandly in a position, which to all appearances, must ere long, become only an intermediate station. The march of events points to s ites on either the line of the Strand, or on that of the New Embankment on the left bank of the Thames, lying between Trafalgar Square and Tem ple Bar, as the ultimate destination of our great lines of railway trending from the North and West. The latter causeway will furnish the finest and most convenient sites in London for railway stations and hotels of the mammoth dimension! now required. The public are hardly yet aware of the great boon they will receive in the opening of this line of route, and with the object in view of fringing it with palatial buildings, they should insist on having a causeway of i 60 feet wide throughout, where possible; the paltry 80 offered by the Metropolitan Board of Works should not be tolerated, seeing that a large space has been reclaimed from the river. Such a thoroughfare, extending from the Victoria Tower, Westminster, to the Tower of London—a crystal Thames on one hand, spanned by troops of exquisite bridges and rows of palaces on the other—would present a coup tfceil unequalled in the great cities of the world. Perhaps the question of greatest interest to the Engineer, in the matter of construction of the season, is that of Bessemer Iron. While so much is known theoretically of its structure and properties, it must be said that practically we are still in the dark about it. This is the more strange, as thousands of tons of the precious metal are being pro duced daily ; in fact the present production of Bessemer iron in all coun tries is 500,000 tons annual, England making twice as much as the rest of the world put together. One of our members, it will be remembered, Mr. Black, read a paper on the subject lately, illustrating it by various curious and interesting specimens in angle iron and rods. A common idea expressed on that occasion was, that a metal capable of such a variety of expression must bo thoroughly understood before being adopted in difficult engineering works. Some of his specimens shown were so knotted and contorted, and that done when in tbo cold state, that the question was at once asked, can such a metal be safe for the compression chord of a girder ? Certainly was the reply, not of that precise degree of softness and ductility; we can make it of any degree of stiffness required. Here it appears is just the difficulty. The metal can be produced in so many different degrees of hardness between that of'extreme pliancy and of extreme shortness, that the engineer who wants 500 tons of it for a long span girder is not sure that he will be supplied with the mass of a perfectly even and equable quality. It will take some years of groping in the dark before the riddle is solved. Then as to rails, whether they are to be made hard or soft ? Make them soft, they yield underthe blow of the wheel, and laminate. Make them hard, and certainly while they live, they will live, but how long will that be ? When the hour of trial comes, they will go like the blade of a penknife. A suggestive commentary on the discussion is that the famous Chalk Farm rail not long ago snapped into three pieces. It was doubtless subject to a fearful ordeal; but still such as a common iron rail would have survived. The snapping occurred at the instant of a collision between two trains on the top of it; all iron structures..are however subject to such exceptional strains, and it is a very generally received opinion, and one which has been lately expressed within the Institute, that steel is more apt to snap under excessive and sudden strains than wrought iron. The sooner this point is cleared up the better; and I do not see that the late experiments of Dr. Fairbairne, exceedingly valu able though they be, reached so far as the point under discussion, whether Bessemer iron of the requisite hardness, when subjected to sudden and great strains, is as reliable as wrought iron. If it pos sesses such a character, surely it may be tested, and its precise measure found, just as simply as the measure of its shearing, tensile, or com pressive strengths to which alone Dr. Fairbairne’s tables refer. The conclusions at which he arrives are, viz.:— The modulus of elasticity for Bessemer Iron within the limits of permanent deflection is equal to that of best W. Iron. The traverse strength of Bessemer Iron is 3| times that of best W. Iron. Tensile strength is .. .. .. 2 „ „ „ Compressive strength is .. .. 2 times the tensile strength *" from which he infers that the most economic form of a steel bar under transverse strain would be one with two flanges, having the bottom flange double the area of the top flange. Another very important point worth investigation, before using Bessemer iron in long span girders and rails is this : does it, as cast iron is believed to do, suffer a diminution of tensile and transverse strength, by being for a long time subject to the vibration caused by the rolling over it of heavy weights. Before leaving this subject, it may be said that the Institute have appointed a Committee to conduct experiments of a similar nature to those of Dr. Fairbairne, on the regular strengths of‘steel and iron, but that they have not yet published their report.
